The intrinsically photosensitive melanopsin-expressing retinal ganglion neurons are important for nonvisual responses to light, such as circadian photoentrainment. These cells, however, require high light intensities to be activated and it has been unclear how photoentrainment to low light levels works. This study finds that rod photoreceptors are essential to photoentrainment at low and middle light intensities.
- Cara M Altimus
- Ali D Güler
- Samer Hattar